Maternal nutrition is important to a developing embryo and to the health of the child later in life. Supplementing the diet with specific vitamins is known to increase health of the foetus for example folic acid (vitamin B9) reduces the risk of spina bifida. However not everything an adult might consume is beneficial to a developing baby. New research published in BioMed Central's open access journal BMC Medicine shows that caffeine is linked to low birth weight babies and that caffeine from coffee in linked to increasing length of pregnancy.